1. Field of the Invention
The invention generally relates to a light-emitting module, and more particularly relates to an organic light-emitting diode (OLED) module.
2. Description of Related Art
An organic electroluminescence display is a self-emissive display. The organic electroluminescence display has the advantages of no viewing angle restriction, low production costs, high response speed (at least one hundred times the response speed of a liquid crystal display), low power consumption, a direct current driving function applicable to a portable device, a wide operating temperature range, light weight, and the ability to be miniaturized together with the hardware. Therefore, the organic electroluminescence device has great potential for development, and is expected to be the new flat panel display in the next generation.
The organic electroluminescence display is composed of two bus lines and an organic light-emitting layer configured between the two bus lines. Generally, the lower bus line is made of a transparent conductive material, such that light generated by the organic light-emitting layer can be transmitted out of the lower bus line. However, the greater the distance from the organic light-emitting layer to an external electrode, the greater the voltage drop-out caused by resistance. This is because the long conductive wire connected between the external electrode and the organic light-emitting layer leads to an increase in the resistance. As such, the less the voltage across the organic light-emitting layer, the lower the luminance.
Based on the above, when the organic electroluminescence display is developed to have an increasing size, the voltage drop-out difference among various regions on the organic light-emitting layer becomes apparent. Thus, the light-emitting uniformity of the display is poor.
The conventional solution to the aforesaid issue often refers to expansion of the cross-section area of the bus line for increasing the amount of power transmission. Alternatively, the contact positions between a flexible circuit board and a substrate can be increased, so as to increase the number of contacts for signal input. Nevertheless, the former solution may result in expansion of the substrate or reduction of the aperture ratio, while the latter solution may increase the volume of the flexible circuit board and the wire bonding costs. Consequently, the above-mentioned issue cannot be efficiently resolved.